Why Deleting Scheduled Jobs with Apex Suddenly Stopped Working March 2015

Question

Any thoughts on why the removeExistingCompletedJobs Method suddenly stopped working around March 2015? We now get an Apex error "Job does not exist or is already aborted" I'm not sure if it coincided with Spring '15 release or not as I wasn't watching closely. Code done by another developer bit over my head with the Cron stuff but I understand it a little.

I know there are other ways to remove scheduled jobs but this had been working fine for past 18 months. Classes are using API 31.0.

Submitted a case but Support hasn't been too helpful since this is in Production so I had to comment out code as a workaround (uncommented here).

    global void execute(SchedulableContext SC){
    queryBalance();

  removeExistingCompletedJobs(sc);
  scheduleNewJobs(sc);

  //Schedule a new batch to retrieve Existing Assignments
  startBatchToRetrieveAssignments();

  //Schedule a new batch to mark assigments as approved or rejected
  startBatchApproveAssignments();

  startBatchToDeleteHit();
}

//=========================================================================//
//Find new jobs and schedule them in the Queue
//=========================================================================//
   for(Schedule__c schedule :lstSchedule){
     schedule.Schedule_Job_Name__c = getJobName(schedule);
     schedule.Schedule_Job_Created__c = true;

     MturkScheduleJobPoster  mturkJobPoster = new MturkScheduleJobPoster(schedule.ID);
     **Id jobID = System.schedule(schedule.Schedule_Job_Name__c, getCronExpression(schedule),
                   mturkJobPoster );  
     schedule.Schedule_Job_ID__c  = jobID;**           
   } 

public void removeExistingCompletedJobs(SchedulableContext SC) {
   List<Schedule__c> lstSchedule = [SELECT Name,  Schedule_Job_ID__c
                                    FROM Schedule__c
                                    WHERE Schedule_Job_Completed__c = true
                                    AND  Schedule_Job_ID__c != null
                                    AND  StartDateTime__c < :System.now()
                                    Limit 100];

   for(Schedule__c schedule :lstSchedule){
       System.abortJob(schedule.Schedule_Job_ID__c);
       schedule.Schedule_Job_ID__c = null;
       schedule.Schedule_Job_Completed__c = false;
       schedule.Schedule_Job_Created__c = false;
       schedule.Schedule_Job_Name__c = null;
   }
   update lstSchedule;  
}

Answer 1

I'm going to assume that the error

"Job does not exist or is already aborted"

is coming from the call to System.abortJob(schedule.Schedule_Job_ID__c);. The System.abortJob method takes a Job_Id parameter. If the Schedule__c.Schedule_Job_ID__c field has an ID that is no longer valid then you will get an error when attempting to abort it.

You could verify the ID first against CronTrigger. If it doesn't exist or has an ERROR or DELETED state you can't abort it.